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[Ornithology • 2017] Myzomela irianawidodoae • A Colourful New Species of Myzomela Honeyeater from Rote Island in eastern Indonesia ---ScRaBBlE

Myzomela irianawidodoae Prawiradilaga, Baveja, Suparno, Ashari, Ng, Gwee, Verbelen & Rheindt, 2017  photo:   Philippe Verbelen  e-journ...

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Showing posts with label Phasianidae - Pheasant. Show all posts
Showing posts with label Phasianidae - Pheasant. Show all posts

Wednesday, March 20, 2019

[Ornithology • 2017] The Role of Niche Divergence and Geographic Arrangement in the Speciation of Eared Pheasants (Crossoptilon, Hodgson 1938) ---ScRaBBlE


 Wang, Liu, Liu, Chang, Wang & Zhang, 2017  DOI: 10.1016/j.ympev.2017.05.003 

Highlights
• The phylogenetic relationship of Eared Pheasants was resolved based on 45 loci.
• Asymmetric historical gene flow occurred between both parapatric and allopatric sister species.
• Allopatric sister species exhibit significantly divergent ecological niches whereas parapatric sister species show niche conservatism.
• Ecological divergence may have been the main factor that promoted ecological niche divergence.

Abstract
One of the most contentious theories in current ecology is the ecological niche conservatism, which is defined as conservatism among closely related species; however, the ecological niche can also be shifted, as documented in several cases. Genetic drift and ecological divergent selection may cause ecological niche divergence. The current study aims to test whether the ecological niche is conserved or divergent and to determine the main factor that drives ecological niche divergence or conservation. We analyzed the phylogenetic relationship, ecological niche model (ENM) and demographic history of Eared Pheasants in the genus Crossoptilon (Galliformes: Phasianidae) to test niche conservatism with respect to different geographically distributed patterns. The phylogenetic relationship was reconstructed using ∗BEAST with mitochondrial cytochrome b (cyt b) and 44 unlinked autosomal exonic loci, and ENMs were reconstructed in MAXENT using an average of 41 occurrence sites in each species and 22 bioclimatic variables. A background similarity test was used to detect whether the ecological niche is conserved. Demographic history was estimated using the isolation with migration (IM) model. We found that there was asymmetric gene flow between the allopatric sister species Crossoptilon mantchuricum and C. auritum and the parapatric sister species C. harmani and Ccrossoptilon. We found that ecological niches were divergent, not conserved, between Cmantchuricum and Cauritum, which began to diverge at approximately 0.3 million years ago. However, the ecological niches were conserved between C. crossoptilon and C. harmani, which gradually diverged approximately half a million years ago. Ecological niches can be either conserved or divergent, and ecological divergent selection for local adaptation is probably an important factor that promotes and maintains niche divergence in the face of gene flow. This study provides a better understanding of the role that divergent selection has in the initial speciation process. The platform combined demographic processes and ecological niches to offer new insights into the mechanism of biogeography patterns.

Keywords: Crossoptilon; Eared-pheasant; Divergent selection; Ecological niche modeling; Genetic drift; Gene flow

Fig. 1. Map of the study area indicating the occurrence points used in for the background similarity test of Ecological Niche Models (ENMs) and the location of DNA samples used in demographic analyses. (The occurrence points (circles) were from bird-watching records (http://birdtalker.net), the Global Biodiversity Information Facility (http://www.gbif.org) and our unpublished survey data. Occurrence points that were far from each other (at least 10 km) and were randomly chosen in ArcGIS software were used for the background similarity test. The study area was the minimal convex polygon of those occurrence points with an additional 200 km. Triangles represent the locations of DNA samples. The area surrounded by the black dashed line was the study area used for the background similarity test. 


Pengcheng Wang, Yang Liu, Yinong Liu, Yajing Chang, Nan Wang and Zhengwang Zhang. 2017. The Role of Niche Divergence and Geographic Arrangement in the Speciation of Eared Pheasants (Crossoptilon, Hodgson 1938). Molecular Phylogenetics and Evolution. In Press. DOI: 10.1016/j.ympev.2017.05.003

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روابط التحميل والمشاهدة، الروابط المباشرة للتحميل
او
شاهد هذا الفيديو القصير لطريقة التحميل البسيطة


كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا
شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا
رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا
شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا
تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا

ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.

[PaleoOrnithology • 2018] Panraogallus hezhengensis • Vocal Specialization through Tracheal Elongation in An Extinct Miocene Pheasant from China ---ScRaBBlE


Panraogallus hezhengensis 
Li, Clarke, Eliason, Stidham, Deng & Zhou, 2018


Abstract
Modifications to the upper vocal tract involving hyper-elongated tracheae have evolved many times within crown birds, and their evolution has been linked to a ‘size exaggeration’ hypothesis in acoustic signaling and communication, whereby smaller-sized birds can produce louder sounds. A fossil skeleton of a new extinct species of wildfowl (Galliformes: Phasianidae) from the late Miocene of China, preserves an elongated, coiled trachea that represents the oldest fossil record of this vocal modification in birds and the first documentation of its evolution within pheasants. The phylogenetic position of this species within Phasianidae has not been fully resolved, but appears to document a separate independent origination of this vocal modification within Galliformes. The fossil preserves a coiled section of the trachea and other remains supporting a tracheal length longer than the bird’s body. This extinct species likely produced vocalizations with a lower fundamental frequency and reduced harmonics compared to similarly-sized pheasants. The independent evolution of this vocal feature in galliforms living in both open and closed habitats does not appear to be correlated with other factors of biology or its open savanna-like habitat. Features present in the fossil that are typically associated with sexual dimorphism suggest that sexual selection may have resulted in the evolution of both the morphology and vocalization mechanism in this extinct species.


Systematic paleontology
AVES Linnaeus, 1758
GALLIFORMES Linnaeus, 1758

PHASIANIDAE Vigors, 1825

Panraogallus hezhengensis gen et sp. nov.

Etymology: The genus name is the pinyin of the Chinese characters meaning ‘coiling’ and the Latin for ‘chicken,’ referring to the preserved elongate trachea in this species. The specific epithet, ‘hezhengensis’ refers to Hezheng area in the Linxia Basin of Gansu Province where abundant fossils, including the holotype, have been collected.

Specimen number: HMV 1876 (HMV, Hezheng Paleozoological Museum, Vertebrate Collection, Gansu Province, China).

Locality and age: Baihua area near Zhuangkeji Township, Guanghe County, Gansu Province, China exposes the Liushu Formation that is late Miocene (7.25–11.1 Ma).





Fig.1 Type specimen of Panraogallus hezhengensis (HMV 1876). It has coiled, super-elongated windpipe and lived in the late Miocene of Gansu Province in northwest China (Photo by Z. LI and reconstruction by X. GUO at IVPP)



Zhiheng Li, Julia A. Clarke, Chad M. Eliason, Thomas A. Stidham, Tao Deng and Zhonghe Zhou. 2018. Vocal Specialization through Tracheal Elongation in An Extinct Miocene Pheasant from China. Scientific Reports. 8, Article number: 8099. DOI: 10.1038/ncomms12739

Song From The Distant Past, A New Fossil Pheasant From China Preserves A Super-Elongated Windpipe english.ivpp.cas.cn/rh/rp/201805/t20180525_192866.html
Song from the distant past, a new fossil pheasant from China preserves a super-elongated windpipe phys.org/news/2018-06-song-distant-fossil-pheasant-china.html via @physorg_com
Song from the distant past, a new fossil pheasant from China preserves a...  bit.ly/2xqnJn4 via @EurekAlert
El esqueleto fosilizado de un faisán con una tráquea súper larga  nationalgeographic.com.es/ciencia/actualidad/esqueleto-fosilizado-faisan-traquea-super-larga_12769 via @natgeoesp


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روابط التحميل والمشاهدة، الروابط المباشرة للتحميل
او
شاهد هذا الفيديو القصير لطريقة التحميل البسيطة


كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا
شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا
رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا
شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا
تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا

ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.

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